THE CANADIAN ENTOMOLOGIST. 17 



Catalogue of Canadian Plants. Part III : Apetal^, by John 

 Macoun, M. A., F. L. S., F. R. S. C, Montreal. 1886. 



The last publication issued by the Geological and Natural History 

 Survey forms the third part of Prof. Macoun's Catalogue of Canadian 

 Plants. Part I., PoLYPETALiE, and Part II., GAMOPETALiE, have already 

 been noticed in these pages. Part III., Apetal^, carries the work on to 

 the end of the Exogens and completes Volume I. 



The value of this important work, which is quite indispensable to 

 every student of Canadian Botany, is much enhanced by the Addendum 

 and comprehensive Index of the whole volume, contained in the present 

 Part. In the former we find corrections and additions to the information 

 recorded under each species in Parts I. and II., so as to bring our know- 

 ledge of the whole of the plants mentioned down to date, and in the latter 

 not only are the orders, genera and species given, but every synonym also 

 appears. 



In the publication of this work Prof Macoun confers a lasting benefit 

 upon the scientific world. No living Botanist has the knowledge of Can- 

 adian plants which he has acquired. Possessed of a keen faculty of 

 observation which almost amounts to an instinct, he has had the advan- 

 tage of travelling extensively and of collecting and studying in their native 

 habitats most of the plants which have been found growing spontaneously 

 in Canada. Moreover, by generously assisting all who apply to him for 

 information, he has secured the hearty co-operation in his work of all the 

 active Botanists in Canada, so that the " Catalogue of Canadian Plants " 

 is not only a record of his own vast experience, which extends over a 

 period of more than 30 years of constant study, but also includes the 

 work of all other collectors and Botanists who have investigated or written 

 upon the Flora of the Dominion. 



So closely are the studies of Botany and Entomology associated 

 together that some knowledge of Botany is actually a necessity to the 

 Entomologist ; particularly is this the case in the interesting work of in- 

 vestigating the life-histories of insects. It frequently happens that a very 

 slight knowledge of the affinities of a given plant may save from starvation 

 valuable larvae which have been transmitted to a distance from the place 

 where their proper food-plant occurs. Most larvae will subsist upon plants 

 of the same genus or others closely allied to them. 



A good instance of this is presented in the numerous Coliades, all of 



